Probes for electrical test instruments such as those known as multi-meters or volt-ohmmeters are a necessary adjunct to most instruments during any testing procedure. The most common interface between the ‘Device Under Test’ (DUT) and the multi-meter is a pointed metallic tip of a probe. The overall length of a conventional probe consists of a pointed shaft and plastic tube-type of enclosure that is usually about 4 to 5 inches long overall, with the tube ½ inch in diameter, and point shaft ¾ inch long and 3/32nd inch in diameter. The user of the probe can contact the DUT with the tip of the point and at the rear of the probe enclosure is either a socket for the lead wire to the multi-meter, or the lead wire is embedded in the tube.
Using two probes allows a multi-meter to read the functions selected by a setting on the multi-meter such as AC or DC volts, amperes, Ohms, frequency, and many other readings as required. The two probes routinely used for electrical and electronic testing require one probe to be held in each hand. One probe, for example, would read the positive DC volts and the other probe reads the negative DC volts to be displayed on the multi-meter.
There are times during testing where it is desirable that one or both of the probes tips, in addition to contacting the DUT with its pointed tip, can also grip onto a lead wire or small terminal of the DUT and remains gripped until released. There are also times when a continuous reading of a function is required and therefore both probes should be used as grips.
Conventional probes are available that have either a point tip or clamp-type of tip, also known as a ‘clip’ or ‘alligator clip’ and some point probes are provided with a separate clip that can be attached to the point. However, attaching the clip is time consuming and can interrupt the concentration and integrity of the testing procedure. A clip is often lost or if a point probe is needed instead of a clamp the point probe may be unavailable. This can lead to the use of the incorrect probe for the test application, with possible damage to the DUT or harm to the user.
Some prior patents provide background to the present invention. For example, U.S. Pat. No. 2,522,810 to Bailey discloses an insulated electrical connector comprising a pair of insulated, spring loaded pivoted jaws.
U.S. Pat. No. 2,918,646 describes a convertible test probe adapted for effecting electrical test contact either by clipping, probing, or sliding contact.
U.S. Pat. No. 4,151,462 to Teyler teaches an electrical test probe having a spring biased clip with an extendable and retractable tip movable within the clip. The normally refracted tip is extendible intermediate spring biased jaws of the electrical probe and is retained in the extended position by a spring bias and the gripping action of the jaws. The housing for the probe includes a compartment for containing interchangeable active or passive circuitry operative upon the signal sensed by the probe or a signal injected thereto from the probe. Apparatus for checking the electrical continuity through the probe is also disposed within the housing. A socket which provides both electrical and structural interconnection between the probe and an attached electrical conductor(s) is disposed at the rear of the housing.
U.S. Pat. No. 7,902,848 to Eccleston, et al. discloses a reversible test probe and test probe tip. In one embodiment, a test probe tip is reversible relative to a test probe body. The reversible probe has a first probe tip at a first end and a second probe tip at a second end. The test probe body has an opening operable to receive the first probe tip and the second probe tip. When the first probe tip is positioned in the opening, the first probe tip is electrically coupled to a metal device in the test probe body. When the second probe tip is positioned in the opening, the second probe tip is electrically coupled to a metal device in the test probe body. In another embodiment, a test probe having two test probe tips is reversible relative to a test lead.
The foregoing patents reflect the current state of the art of which the present inventor is aware. Reference to, and discussion of, these patents is intended to aid in discharging Applicant's acknowledged duty of candor in disclosing information that may be relevant to the examination of claims to the present invention. However, it is respectfully submitted that none of the above-indicated patents disclose, teach, suggest, show, or otherwise render obvious, either singly or when considered in combination, the invention described and claimed herein.